c-- ccc ccd ccn cco ccp cdc cdd cdn cdo cdp cn- cnc cnd cnn cno cnp co- coc cod con coo cop cpc cpd cpn cpo cpp dcc dcd dcn dco dcp ddc ddd ddn ddo ddp dnc dnd dnn dno dnp doc dod don doo dop dpc dpd dpn dpo dpp ncc ncd ncn nco ncp ndc ndd ndn ndo ndp nnc nnn nno nnp no- noc nod non noo nop npc npd npn npo npp oc- occ ocd ocn oco ocp odc odd odn odo odp on- onc ond onn ono onp oo- ooc ood oon ooo oop op- opc opd opn opo opp p-p pcc pcd pcn pco pcp pdc pdd pdn pdo pdp pn- pnc pnd pnn pno pnp poc pod pon poo pop ppc ppd ppn ppo ppp